Releasable backstop for conveyor rollers

ABSTRACT

An internally powered conveyor roller, of the type used for driving a conveyor one direction, and for preventing movement in opposite direction and having a drive roller for driving the conveyor medium, an internal drive motor for driving the roller, a one-way rotation device permitting rotation of the roller in one direction, and for preventing rotation in the opposite direction, and the one way rotation means being moveable between engaged and disengaged positions, and when in the disengaged position, being inoperative to prevent reverse rotation of the roller.

TECHNICAL FIELD

The invention relates to rollers for conveyor systems, and in particularto an internal drive conveyor roller system having a backstop, oranti-reverse movement check, and in which the backstop can be releasedin certain circumstances to allow reverse movement of the conveyorsystem.

BACKGROUND ART

Many conveyors are designed around a systems of conveyor chains or meshscreens, or in some cases, conveyor belts. These conveyor “media” may besupported on simple shafts on which may be mounted various forms ofsprockets, or drive means for supporting the conveyor media. Moreadvanced conveyor systems are known using enclosed and sealed driverollers with the drive motors contained inside the rollers themselves.

The use of internal drives for the conveyor rollers is particularlyadvantageous in many situations where conveyors are required. In thesesystems the rollers usually carry a conveyor belt or conveyor chains orsome similar supports, which run over the rollers and which carry loaditems or product to be conveyed.

Food product conveyors are a typical example where such internal driverollers are used, although the invention is not restricted to such use.

The roller drives are located inside the drive rollers themselves, andare sealed, and are not liable to contamination from the product beingcarried, and furthermore the product itself will not be contaminated bythe drive system, which may require lubricants, and which may accumulatedirt, if exposed.

In many situations, parts of the conveyor system will run level, but atother locations the conveyor system runs at an angle. In these locationsthe conveyor belts or chains are required to run along an uphillincline. In these cases if the incline conveyor is halted for anyreason, the weight of product will tend to cause the incline conveyor torun in reverse. If this is allowed to occur, the product will movebackwards and will accumulate at the bottom of the incline conveyor, andprobably collect at the leading end of the preceding level portion ofthe conveyor system.

This will in most cases damage the load items or product and will causedowntime on the system while the problem is corrected. In order toprevent this from happening it is known to provide the incline conveyor,in one of the rollers, with what is known as a “backstop”. This issimply a form of dog clutch or brake, which allows rotation in theforward direction, ie with the conveyor running up the incline, butprevents rotation in the reverse direction. By the use of this backstopdevice reverse movement of the incline conveyor cannot take place. Ifthe conveyor system stops for any reason, the incline conveyor willsimply remain stationary, without moving or slipping backwards.

While this device solves the problem of unwanted reverse movement, thereare some cases where the operator of the conveyor system will want tooverride the backstop. The operator for whatever reason wishes to permitthe conveyor to move in reverse. However the effect of the backstop isto prevent this altogether.

Clearly therefor in order to satisfy customer requirements it isdesirable to provide a backstop which is normally engaged, and whichthus prevents reverse movement, but which can be disengaged by theoperator, in situations where he wishes the conveyor to move in reverse.

DISCLOSURE OF THE INVENTION

With a view to satisfying the foregoing requirements the invention sprovides an internally-powered conveyor roller, of the type used fordriving a conveyor medium in a first predetermined direction, and forpreventing movement in a second direction opposite to the first andhaving roller means for carrying the conveyor medium, internal drivemeans for driving the roller means, one-way rotation means forpermitting rotation of said roller means in one direction, and forpreventing rotation in the opposite direction, and, said one wayrotation means being moveable between engaged and disengaged positions,and when in said disengaged position, being inoperative to preventreverse rotation of said roller means.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said roller means includes acylindrical drum, and end discs closing each end of the drum, and motormeans located within said drum.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said end discs incorporatehubs and mounting shafts extending through said hubs for mounting saidroller means in position in a conveyor system.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said motor means drives saiddrum through reduction gear means within said drum.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said one-way rotation meansincludes a body member engageable with said motor drive means forcontrolling one way rotation thereof, and means for moving said bodymember into a disengaged position wherein said motor is free to rotatein either direction.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said body member is enclosedwithin a ring member and including rod means connected to said ringmember and extending therefrom axially of said drum and through saiddisc member at one end of said drum, and means for operating said rodmember to draw the same outwardly or to return it inwardly, therebydiseasing said body member from said motor shaft upon outward movementand re-engaging said body member with said motor shaft upon returnmovement of said rod member.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said body member is formedwith spaced apart roll recesses and rolls moveably located in respectiverecesses, and said rolls moving inwardly within said recesses uponrotation in one direction, and said rolls moving outwardly of saidrecesses upon reverse movement, thereby contacting and binding againstsaid ring member and preventing further such reverse movement.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said motor shaft is formedwith a splined end portion and wherein said body member is formed withan internally splined recess for receiving said splined end, when insaid engaged position.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein a support shaft is securedto said disc member closing said drum at one end thereof, and said shaftmember defining a hollow interior and wherein said rod member is locatedwithin said hollow shaft member.

The invention further provides an internally powered conveyor rollerhaving the foregoing advantages and wherein said rod member is providedwith means for grasping the outwardly extending portion of said rodmember and manually drawing said rod member outwardly as aforesaid.

The various features of novelty which characterize the invention arepointed out with more particularity in the claims annexed to and forminga part of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its use,reference should be had to the accompanying drawings and descriptivematter in which there are illustrated and described preferredembodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic sectional side elevation, partially cut away andshortened, of a conveyor roller, with an internal drive, andillustrating one embodiment of the invention in the form of a releasablebackstop;

FIG. 2 is an enlarged sectional side elevation of a portion of theconveyor roller of FIG. 1 showing the releasable backstop in its engagedposition;

FIG. 3 is a sectional side elevation corresponding to FIG. 2 but showingthe releasable backstop in its disengaged position, and,

FIG. 4 is a section along line 4—4 of FIG. 3.

MODES OF CARRYING OUT THE INVENTION

As explained above the invention finds its application as part of aconveyor system. Such conveyors may be found in many differentapplications. One significant aspect of such conveyor systems is thatthey are designed around conveyor rollers which carry the conveyormedium. This may be a belt, or a series of conveyor supports such aschains. The drive rollers in such a conveyor system which are powered soas to drive the conveyor medium are internally driven. That is to saythe drive rollers contain within the roller drum, the drive motor and inmost cases, reduction gears. The entire drum is sealed so that alllubricants are retained within the interior of the drum, and all outsidecontaminants are excluded. The only connection to the exterior isprovided by support shafts extending from each end of the roller, andelectrical connections by which power is supplied to the drive motorwithin the drum.

Clearly not all rollers in such a system are power driven. Some are idlerollers which function simply to support the conveyor medium. However inthis case also the rollers are sealed so that there is no contamination.

Where the conveyor system is required to elevate the load items,referred to herein as “product”, then a length of the conveyor isprovided which runs at an angle, on an incline. Conveyor segments ateach end of the incline will usually be level.

As explained in such incline sections the powered roller is providedwith a backstop, or anti-rollback device. This functions to preventreverse movement of the inclined conveyor, if the conveyor is stoppedfor any reason.

The invention is directed to the provision of such a backstop devicewhich can be manually disengaged, or re-engaged as required by theoperator.

Referring to FIG. 1 the invention is illustrated in the form of apowered roller 10. It is understood that such roller 10 is to be locatedsomewhere in a conveyor system where the conveyor medium is inclined.Roller 10 would thus normally be supported on a framework (not shown) ofa type well known in the art and requiring no description. A conveyormedium such as a belt or chains or the like (not shown) would run aroundroller 10 in a manner well known in the art.

Idle rollers (not shown) would also be provided so that the conveyormedium runs around a continuous path in a manner well known, and issupported in a manner adequate for the product being carried. Usuallythe driven roller will be at one end of the conveyor segment, either thelower or upper end.

The roller 10 is provided with a cylindrical hollow drum 12, which issupported at each end by respective left and right end discs 14 and 16.Left disc 14 has a central hub 18 supporting a bearing 20 and right disc14 has a hub 22 supporting a bearing 24.

An electrical drive motor is indicated generally as 26. It is mountedwithin the interior of drum 12 and is supported between a left endhousing 28 and a right end housing 30. The drive housings and motor areknown per se and are held together as a unit by threaded rods 32. Adrive shaft 34 extends through motor 30 and through both left and righthousings 28 and 30.

The left end of shaft 34 is formed with shaft gear teeth 36. A reductiongear 38 is mounted in left end housing 28 and is driven by shaft teeth36.

Gear 38 has a gear shaft 40, formed with reduction teeth 42. Teeth 42engage a drum drive gear 44, formed on left hub 18 of the left end disc16. Drum gear has external teeth 46. The location and number of teeth 46can vary from one application to another. While the teeth 46 are shownon an inner portion of hub 18, which is in effect in the position of asun gear in an epicyclic system, it will be appreciated that hub 18 canbe formed with a much larger gear ring (not shown) having internalteeth, which would be in effect in the position of the ring gear of anepicyclic system. Such a ring gear would have many more teeth, than thecentral sun-type gear shown, and so a greater speed reduction would beobtained.

A left roller mounting shaft 48 is received in the left hub 18, thuspermitting the left end of the roller to be mounted and secured on asuitable frame or support, at a desired location in the conveyor system.Electrical connection box 50 is fastened adjacent the left end of roller10, and wires W extend through the left end mounting shaft (not shown)for supplying power to the motor.

Attached to the right motor housing 30 is the backstop housing 52.Housing 52 defines an annular flange 54 by which it is bolted to rightmotor housing 30. Extending from flange 54 is shaft connector sleeve 56.A right mounting shaft 58 is secured in sleeve 56 and extends axiallythrough drum 12 and out through right disc hub 22. Bearings 24 in dischub 22 ride on shaft 58 permitting rotation of drum 12 relative to shaft58. Suitable seals are provided to prevent exiting or entry ofcontaminants. Shaft 58 may be secured at the right end of the roller 10to a frame or support, in a suitable location in the conveyor system.

Within backstop housing 52 a hollow interior chamber 60 is defined.Right motor housing 30 also defines a recess 62 of similar diameter tochamber 60.

Motor shaft 34 extends into the interior of recess 62 and is formed withsplines 64 on its free end.

A control rod 66 extends through the hollow interior of right mountingshaft 58. At its right end rod 66 it extends out of shaft 58 and isprovided with threaded bore 68. A plug 70 is received in bore 68 of rod66.

At the inboard or left end of control rod 66 there is a backstop endplate secured to rod 66. A cylindrical ring 74 extends from plate 72 isnormally received in the recess of 62 of right motor housing 30.

Dowel pins 75 are located within motor housing 30 around chamber 62.Ring 74 has recesses registering with the dowel pins and is thus lockedagainst rotation relative to housing 30. However ring 74 is slideablealong pins 75 out of between recess 60 and 62 for reasons to bedescribed below. Within ring 74 a one way backstop bearing body 76 islocated. Body 76 is generally annular and carries within it a drive body77 having a central splined recess 78. Recess 78 normally receivessplined end 64 of motor shaft 34. Both body 76, and drive body 77 withits central splined recess 78 are retained together with a key (knownper se) to prevent relative rotation and retained by retaining circlip Cto secure it in its axial location. When the shaft end is received inthe recess 78 in body 76, shaft 34 and body 76 are locked together.

Body 76 supports a plurality of backstop rolls 80 in respective angledrecesses 82. A ring 81 surrounds body 76 and rolls 80. Within theirrespective recesses 82 rolls 80 are movable outwardly and inwardlyrelativ to body 76. In their outer position the rolls 80 engage theinner surface of ring 81, and wedge securely against it preventingmovement of body 76 relative to ring 81.

Ring 81 is itself secured within ring 74, by a press fit.

Body 76 is retained in ring 74 by a retention circlip 84, leaving body76 free to rotate in one direction, within ring 74, as described,without restriction from the circlip 84.

Ring 74 as explained above, is locked within chamber 62 of housing 30 bydowel pins 75. When in their inward positions the rolls 80 roll freely,out of wedging contact within ring 81, and permit rotation of body 76relative to ring 81. In this way when motor 26 is driving its motorshaft 34 normally, body 76, which is locked to shaft 34 by spline end 64in recess 78 is free to rotate within ring 81, in the driving direction.Dowel pins 75 will prevent backstop ring 74 and plate 72 from rotationalmovement and thus the entire backstop assembly holds the motor shaft 34against reverse rotation, while allowing forward rotation.

However, as stated above the dowel pins 75 allow ring 74 to move axiallyinto recesses 62 and back into chamber 60.

Under normal operation, in the event of a shut down of motor 26 for anyreason, any attempt by drum 18 to rotate in reverse is prevented. Thisbecause body 76 remains locked to shaft 34, and is wedged againstreverse rotation by the wedging engagement between rolls 80 and ring 81.

Body 76 and the splined recess 78 are normally engaged with the splinedrecess end of 64 motor shaft 34.

In order to permit manual disengagement, of body 76 from splined end ofshaft 34, the rod 66, on which plate 72 is secured, is slidable withinshaft 58, as can be seen by comparing FIG. 2 and FIG. 3.

In order to permit manual sliding of rod 66, the plug 70 is unthreadedand removed.

A handle member, or knob 86, having a threaded stem 88 is inserted inthe threaded recess in the exposed end of shaft 58. By simply pulling onthe knob 86 the rod is slid axially within shaft 58. This will drawplate 72, ring 74, and body 76 away from splined end 64 of shaft 34. Thesplined end 64 will then no longer be received in the splined recess 78of drive body 77, and will not be subject to the one way reversechecking action of body 76, and rolls 80, described above.

In the event of the motor shutting down for any reason the motor shaftwill now be free to rotate in the reverse direction, and thus permit theconveyor segment to move in reverse.

Clearly the body 76 can be re-engaged with splined end 64 by simplypushing the rod 66 inwardly.

By this means the conveyor roller is provided with a one way backstopwhich normally prevents reverse rotation of the roller, but whichbackstop can be disengaged whenever it is not required, thus providingthe operator of the system with the flexibility of both modes ofoperation.

The foregoing is a description of a preferred embodiment of theinvention which is given here by way of example only. The inventionwhich is not to be taken as limited to any of the specific features asdescribed, but comprehends all such variations thereof as come withinthe scope of the appended claims.

What is claimed is:
 1. An adsorbent for cardiac glycoside contained inbody fluid, comprising a compound which is immobilized on awater-insoluble carrier and has a log P value of at least 6, wherein Pis a partition coefficient in an octanol-water system.
 2. The absorbentof claim 1, wherein said water-insoluble carrier is a water-insolubleporous carrier.
 3. The absorbent of claim 2, wherein saidwater-insoluble porous carrier has an exclusion limit for globularprotein of at most 600,000.
 4. The absorbent of claim 1, wherein thecardiac glycoside is digitalis.
 5. A process for absorbing and removingcardiac glycoside contained in body fluid, which comprises contactingbody fluid with an adsorbent for cardiac glycoside comprising a compoundwhich is immobilized on a water-insoluble carrier and has a log O valueof at least
 6. 6. An absorber for cardiac glycoside which comprises acontainer having an inlet and an outlet for fluid and a means forpreventing an adsorbent from flowing out of the container, wherein theadsorber is filled with the adsorbent for cardiac glycoside comprising acompound which is immobilized on a water-insoluble carrier and has a logP value of at least
 6. 7. An internally powered conveyor roller asclaimed in claim 6 and wherein said body member is formed with spacedapart roll recesses and rolls moveably located in respective recesses,and said rolls moving inwardly within said recesses upon rotation in onedirection, and said rolls moving outwardly of said recesses upon reversemovement, thereby contacting and binding against said ring member andpreventing further such reverse movement.
 8. An internally poweredconveyer roller as claimed in claim 7 and wherein said motor shaft isformed with a splined end portion and wherein said body member is formedwith an internally splined recess for receiving said splined end, whenin said engaged position.
 9. An internally powered conveyer roller asclaimed in claim 8 and wherein a support shaft is secured to said discmember closing said drum at one end thereof, and said shaft memberdefining a hollow interior and wherein said rod member is located withinsaid hollow shaft member.
 10. An internally powered conveyer roller asclaimed in claim 9 and wherein said rod member is provided with meansfor grasping the outwardly extending portion of said rod member andmanually drawing said rod member outwardly as aforesaid.